在句子中起宾语作用的从句叫做宾语从句.宾语从句分为三类：动词的宾语从句,介词的宾语从句和形容词的宾语从句.
宾语从句的连接词：
(一)、从属连词
连接宾语从句的从属连词主要有that,if,whether.
that引导表示陈述句的宾语从句,
if和whether,whether...or not引导表示“是否”的一般疑问句的宾语从句.
（二）关联代词
连接代词主要有who,whom,whose,what,whoever,whomever,whosever,whatever,whichever等.
连接代词一般指疑问,但what,whatever除了指疑问外,也可以指陈述.
（三）关联副词
连接副词主要有when,where,why,how,whenever,wherever,however等.
宾语从句的用法 1．that引导宾语从句无意义,不充当句子成分常省略.但下列情况除外：
①．介词宾语从句的that不能省略.
②． and连接的两个从句,两个从句的that不能省略.
He told me that he had two sons and that they both had gone to college.
③．在动词+it+宾语补足语+宾语从句结构中,that不省略.
I heard it said that he had gone abroad
We found it impossible that he could finish it in such a short time
2.Whether,if 引导宾语从句：两词可互换,但是下列情形除外：
①．whether从句中有or not
②．whether从句做介词宾语
Everything depends on whether you agree with us
3．许多带复合宾语的句子,宾语从句经常移到句子后部,而用it做形式宾语.结构是：
主语 + 动词 + it + 形容词/名词等宾语补足语 + 宾语从句
We think it wrong that he told a lie to everyone.
①．宾语从句的语序要用陈述句语序.
False: He is wondering when can he finish this difficult job.
Right: He is wondering when he can finish this difficult job.
②. 有时候可以用it 作形式宾语,而把真正的宾语从句放在后面.
Bad: I thought that he could finish this job in just two hours impossible.
Good: I thought it impossible that he could finish this job in just two hours.
Bad: He left whether we should continue this project to my judgment.
Good: He left it to my judgment whether we should continue this project.
③. 带有宾语从句的复合句的否定形式一般是否定主句.
Bad: I think he doesn’t like the English teacher.
Good: I don’t think he likes the English teacher.
④. 主句一般过去时态,从句也要用过去时态；具体细节请看第一部分.
False: He wanted to know why he is crying in the corner.
Right: He wanted to know why he was crying in the corner.
希望可以帮到你.
